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" Effect of gossypol on reproductive function in mammals "
M. Muhammad
Y. C. Lin
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Latin Dissertation
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| Language of Document
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English
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| Record Number
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1113291
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| Doc. No
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TLpq304201713
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| Main Entry
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M. Muhammad
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Y. C. Lin
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| Title & Author
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Effect of gossypol on reproductive function in mammals\ M. MuhammadY. C. Lin
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| College
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The Ohio State University
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| Date
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1995
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| student score
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1995
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| Degree
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Ph.D.
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| Page No
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236
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| Abstract
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The present study evaluated effects of in vitro treatment of gossypol (GP) on testosterone (T) secretion in rat, dog, boar, and bull testicular interstitial cells as well as progesterone and estradiol secretion in porcine granulosa cells. In addition, changes in progesterone secretion induced by GP were assessed in luteal cells collected at known stages of early pregnancy and at undefined stages of reproduction in sows. Biological activities of GP metabolite, gossypolone (GN) and that of milk obtained from GP-treated dairy cows (GP-milk) were tested and compared to GP regarding effects on ovarian function. Along with the endocrine data, effects of GP on porcine oocyte maturation, cleavage of matured oocytes and fertilizability of sperms were also determined. The results demonstrated inhibition of hCG-stimulated T secretion by GP in cultured testicular interstitial cells in dogs and boars (0.5 and 2.5 muM), and rat and bull (5.0 muM). GN was found to possess an equivalent potency as compared to GP in inhibiting oocyte maturation (2.5muM) and decreasing progesterone secretion (5.0 muM) in cultured porcine granulosa cells. 50% GP-milk was found to exert the same antisteroidogenic activity as of 5.0 muM of either GP or GN. Collectively, the results demonstrate that GP suppresses sperm fertilizability, maturation and cleavage in oocytes and decreases both testicular as well as ovarian steroidogenic activities. Based on these results, it is concluded that long-term administration of GP, GN, or GP-milk may lead to disturbances in estrus, ovulation, and pregnancy in females as well as in libido and spermatogenesis in males of both monogastric and non-monogastric animals. The exact mode of action of GP (GN or GP-milk) in inhibiting gonadal steroidogenesis and embryo formation is not clearly understood. It is speculated that inhibition of steroidogenesis may result from expression of an inhibitory factor (TGFusd\betausd) induced by GP in the gonads, while prevention of embryo formation may be due to suppression of RNA and protein synthesis by GP. Further studies are needed to reach better understanding of the mechanism of action of GP in affecting these functions.
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Animal diseases
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Biological sciences
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Livestock
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Livestock
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